Jerome Brown, the Philadelphia Eagles' star defensive tackle, and his 12-year-old nephew were killed yesterday afternoon in his hometown of Brooksville, Fla., when the 1992 Corvette Brown was driving skidded out of control on wet pavement, hit a palm tree and overturned, the police said.

Brown, 27 years old, was speeding before the crash on Hale Avenue in Brooksville, according to a witness who refused to give his name. The witness said it had been raining earlier in the day, but that it was not raining when the accident occurred at approximately 4:45 P.M. Brown and his 12-year-old nephew, whose name was not released, were pronounced dead at 5 P.M. 'The Car Was Destroyed'

"The car skidded off the left side of the road for about five car lengths before it hit the tree," the witness said. "The car was destroyed and there was damage everywhere. I could see part of his head and shoulders in the car and part of the boy's body. They must have died instantly."

Brown lived in Brooksville during the off season.

He was an all-American at the University of Miami and the Eagles' No. 1 draft pick -- the ninth pick over all -- in the 1987 National Football League draft. In his six pro seasons, Brown earned Pro Bowl berths in 1990 and in 1992. Brown, along with linemen Reggie White, Clyde Simmons and Mike Pitts, had helped the Eagles form one of the league's most ferocious defensive fronts. Brown had helped lift the Eagles' defense last season to the No. 1 ranking in the league against the rush, against the pass and in total defense. A Flamboyant Style

At Miami and in Philadelphia, Brown was noted for his flamboyant style, outspoken manner and emotional and spirited play.

Brown's former Eagles coach, Buddy Ryan, said: "He was the best defensive lineman in the league. He wound the team up on game day. I went down and drafted him because he was our kind of player. He was a personable young man.

"The first night he came to Philadelphia, he went to an event with us against the cruelty of animals. That's the kind of person he is. The Eagles will miss his leadership."

Rich Kotite, the Eagles' current coach, said: "Right now, I don't know what to say. I'm just shocked. Jerome was such an outstanding and dynamic guy. He had the biggest heart of any man I've ever known."

Joe Woolley, the Eagles' director of player personnel, said that he and Brown had many private talks and always chided each other.

Woolley added: "He had a heart of gold. I helped bring Jerome here in 1987 and that's something I will always remember. With his passing, I feel like a little bit of me is gone, too."

Photo: Officials examining the car in which Eagles' Jerome Brown and his nephew were killed yesterday in Brooksville, Fla., below. (Associated Press) Map of Florida showing location of Brooksville.

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